The pony is unfortunately dead, put to sleep (10)
I believe the answer is:
hypnotised
'the pony is unfortunately dead put to sleep' is the definition.
I can't judge whether this definition defines the answer.
'the pony is unfortunately dead' is the wordplay.
'unfortunately' indicates an anagram (a bad or unfortunate spelling).
'dead' becomes 'd' (abbreviation in government records).
'the'+'pony'+'is'='theponyis'
'theponyis' is an anagram of 'hypnotise'.
'hypnotise'+'d'='HYPNOTISED'
Can you help me to learn more?
(Other definitions for hypnotised that I've seen before include "Mesmerised" , "in a trance!" , "Put under" .)